Bulletin of the American Physical Society
2017 Annual Spring Meeting of the APS Ohio-Region Section
Volume 62, Number 6
Friday–Saturday, May 5–6, 2017; Ypsilanti, Michigan
Session D4: Contributed: Particle and Nuclear Physics |
Hide Abstracts |
Chair: David Pawlowski, Eastern Michigan University Room: Pray-Harrold 305 |
Saturday, May 6, 2017 8:36AM - 8:48AM |
D4.00001: GPU-Accelerated Lanczos Diagonalization Juan Manfredi Nuclear structure calculations involve the diagonalization of a symmetric Hamiltonian matrix. The Lanczos algorithm is typically used to calculate a tridiagonal matrix (which is then easily diagonalizable) similar to the original Hamiltonian. Graphics processing units (GPUs) are particularly well suited for the sparse matrix-vector multiplications involved in Lanczos diagonalization. Although modern GPUs have limited onboard memory, future generations could be valuable for performing cutting-edge structure calculations. In this work, the Lanczos algorithm is implemented and evaluated on a GPU with a variety of sparse matrix-vector multiplication algorithms. [Preview Abstract] |
Saturday, May 6, 2017 8:48AM - 9:00AM |
D4.00002: The Quark-Hadron Phase Transition in Neutron Stars and Protoneutron Stars Jacob Roark Neutron stars have masses between 1.4 and 3 M$_{\odot}$, all packed into a sphere just 12 to 13 km across. Consequently, neutron stars exhibit some the of highest material densities in the universe, averaging around 7$\times$10$^{17}$ kg/m$^3$, over three times the density of an atomic nucleus. Under such astronomical pressures, some very interesting, novel states of matter can be achieved, such as quark matter. In this project, the quark-hadron phase transition was studied in the constext of neutron stars and protoneutron stars, along with the possibility of a mixture of phases. An effective model based on the spontaneous breaking of chiral symmetry was employed to achieve this data, along with a mean field approximation. In each case, the point at which phase transitions no longer occur (the critical point) was found, characterized by temperature and baryon chemical potential. For neutron stars, the critical point was found to occur at T=168.82 MeV and $\mu_{B}$=230.05 MeV and at T=168.86 MeV and $\mu_{B}$=226.50 MeV when allowing for a mixture of phases. For protoneutron stars, the critical point was found to occur at T=168.82 MeV and $\mu_{B}$=247.25 MeV and at T=168.00 MeV and $\mu_{B}$=315.50 MeV when allowing for a mixture of phases. [Preview Abstract] |
Saturday, May 6, 2017 9:00AM - 9:12AM |
D4.00003: On HQET and NRQCD Operators of Dimension 8 and Above Malawara Arachchige Ayesh Gunawardana, Gil Paz Effective field theories such as Heavy Quark Effective Theory (HQET) and Non Relativistic Quantum Chromo-(Electro-) dynamics NRQCD (NRQED) are indispensable tools for controlling the effects of the strong interaction. The increasing experimental precision requires the knowledge of higher dimensional operators. These operators are important to the evaluation of decay rates of the B-meson. We present a general method that allows for an easy construction of HQET (NRQED and NRQCD) operators that contain two heavy quark (non-relativistic) fields and any number of covariant derivatives. As an application of our method, we give for the first time all such terms in the $1/M^4$ NRQCD Lagrangian, where $M$ is the mass of the spin-half field. We analyze the general dimension-nine spin-independent HQET matrix element, which was not considered so far in the literature, and calculate moments of the leading power shape function up to and including dimension nine HQET operators. [Preview Abstract] |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700